Transition duct installation

I removed the deteriorated foil-flex ductwork at this San Francisco residence due to excessive lint accumulation and airflow restriction, then installed a new 2158a fire-rated transition duct to connect the dryer to the wall-mounted vent outlet. The interior wall cavity was cleaned of lint buildup, and the new ductwork was sealed and secured to code-compliant standards. These repairs restored proper venting performance and eliminated the fire hazard created by the compromised original system.